Deflectable catheter with hinge

ABSTRACT

A deflectable device, such as a catheter, is provided that includes a hinge that enhances the ability of the device to deflect or bend within a predetermined plane. The catheter comprises an elongated tubular catheter body having proximal and distal ends and at least one lumen extending therethrough. A distal segment is provided distal to the distal end of the catheter body. A tubular hinge is provided between the distal end of the catheter body and the proximal end of the distal segment. The hinge has an axis and at least one lumen extending therethrough. The tube includes at least one slot, and preferably a plurality of slots, extending part of the way through the hinge generally transverse to the axis of the hinge.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is a continuation of and claims priority to and thebenefit of U.S. application Ser. No. 14/320,124 filed Jun. 30, 2014, nowU.S. Pat. No. 9,636,482, which is a continuation of and claims priorityto and the benefit of U.S. application Ser. No. 11/866,352, filed Oct.2, 2007, now U.S. Pat. No. 8,764,743, which is a continuation of andclaims priority to and the benefit of U.S. application Ser. No.10/386,868, filed Mar. 12, 2003, now U.S. Pat. No. 7,276,062, the entirecontents of all of which are incorporated herein by reference.

FIELD ON THE INVENTION

The present invention relates to an improved catheter having a hinge toenhance the ability of the catheter to bend in a desired direction.

BACKGROUND OF THE INVENTION

Deflectable catheters are widely used for a variety of applications. Inthe area of electrophysiology, it is often desirable to introduce aportion of a catheter carrying one or more electrodes into a certainregion of the heart in order to map or ablate that region. However, dueto their inherent flexibility, catheters can be difficult to control asprecisely as would be desired. Accordingly, a needs exists for adeflectable catheter having a mechanism to enhance the user's ability tocontrol the degree and direction of deflection of the catheter.

SUMMARY OF THE INVENTION

The present invention provides deflectable devices, such as catheters,that include a hinge that enhances the ability of the device to deflector bend within a predetermined plane. In one embodiment, the inventionis directed to a deflectable device comprising an elongated tubinghaving proximal and distal ends, an axis, at least one lumen extendingtherethrough and a distal region at or near the distal end of thedeflectable device. The tubing, which can be a single tubing or aplurality of connected tubing segments, includes at least one slotextending part of the way through the tubing in the distal region. Theat least one slot is generally transverse, and preferably generallyperpendicular, to the axis of the tubing. The device further includesmeans for deflecting the distal region of the tubing in a plane thatpasses through the at least one slot.

In another embodiment, the invention is directed to a deflectable devicehaving proximal and distal ends. The device comprises a proximal regionnear the proximal end of the device and a distal region near the distalend of the device. A hinge is provided between the proximal and distalregions. The hinge comprises a tubing having an axis and at least onelumen extending therethrough. The tubing includes at least one slotextending part of the way through the tubing.

In yet another embodiment, the invention is directed to a deflectablecatheter. The catheter comprises an elongated tubular catheter bodyhaving proximal and distal ends and at least one lumen extendingtherethrough. A distal segment is provided distal to the distal end ofthe catheter body. A tubular hinge is provided between the distal end ofthe catheter body and the proximal end of the distal segment. The hingehas an axis and at least one lumen extending therethrough. The hingeincludes at least one slot extending part of the way through the hingegenerally transverse to the axis of the hinge.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features and advantages of the present invention will bebetter understood by reference to the following detailed descriptionwhen considered in conjunction with the accompanying drawings wherein:

FIG. 1 is a side view of an embodiment of the catheter of the invention.

FIG. 2 is a side cross-sectional view of a catheter body according tothe invention, including the junction between the proximal and distalregions of the catheter shaft of the catheter shown in FIG. 1.

FIG. 3 is a side view of the intermediate and distal shafts of thecatheter shown in FIG. 1.

FIG. 4 is an end cross-sectional view of the intermediate shaft shown inFIG. 3.

FIG. 5 is a perspective view of a hinge according to the invention in aneutral configuration.

FIG. 6 is a perspective cutaway view of the hinge depicted in FIG. 5.

FIG. 7 is a top view of the hinge depicted in FIG. 5.

FIG. 8 is a side view of the hinge depicted in FIG. 5.

FIG. 9 is a side view of the hinge depicted in FIGS. 5 to 8 in adeflected configuration.

FIG. 10 is an end cross-sectional view of the distal shaft shown in FIG.3.

FIG. 11 is a cross sectional view of a portion of the catheter tipsection showing one means for attaching the puller wire.

FIG. 12 is a top cross sectional views of a preferred puller wireanchor.

FIG. 13 is a side cross sectional views of the puller wire anchor ofFIG. 12.

DETAILED DESCRIPTION OF THE INVENTION

The invention is directed to a deflectable device, such as a catheter,including a hinge that enhances the ability of the device to deflect orbend within a predetermined plane. In accordance with the invention, thedevice can be deflected or bent upon application of a pulling force fromwithin the device, such as by the use of a puller wire as is generallyknown in the art, or the device can be bent upon application of anoutside force on a part of the device, such as by pushing a part of thedevice again tissue to cause the tissue to thereby exert a force onto apart of the device and bend that part of the device relative to the restof the device. As used herein, the term “deflectable” describescatheters having a straight configuration in the neutral position thatcan be deflected into a curved configuration, as well as cathetershaving a curved configuration in the neutral position that can bedeflected into a straight configuration or into a different curvedconfiguration.

In one embodiment of the invention, there is provided a steerablecatheter having an irrigated electrode at its distal end. As shown inFIG. 1, the catheter comprises an elongated catheter shaft 12 havingproximal and distal ends, an intermediate shaft 14 at the distal end ofthe catheter shaft over which the hinge is mounted, a distal shaft 16 atthe distal end of the intermediate shaft on which one or more electrodesor other devices are mounted for performing mapping, ablation or anotherdesired function, and a control handle 18 at the proximal end of thecatheter shaft.

In the depicted embodiment, the catheter shaft 12 has a proximal region20 and a distal region 22 having different degrees of flexibility. Sucha design is particularly useful where it is desired to deflect thedistal region 22 of the catheter shaft. Typically the proximal region 20is substantially longer than the distal region 22, with the proximalregion having an exemplary length ranging from about 90 cm to about 120cm, and the distal region having an exemplary length ranging from about1 cm to about 8 cm.

With reference to FIG. 2, the proximal region 20 of the catheter shaft12 comprises an elongated tubular construction having a single, axial orcentral lumen 24. The proximal region 20 is flexible, i.e., bendable,but substantially non-compressible along its length. The proximal region20 can be of any suitable construction and made of any suitablematerial. A presently preferred construction comprises an outer wall 26made of polyurethane or PEBAX. The outer wall 26 comprises an imbeddedbraided mesh of stainless steel or the like to increase torsionalstiffness of the proximal region 20 so that, when the control handle 18is rotated, the distal region 22 of the catheter shaft 12 will rotate ina corresponding manner.

Additionally, in the depicted embodiment, the inner surface of the outerwall 26 of the proximal region 20 is lined with a stiffening tube 28,which can be made of any suitable material, preferably polyimide. Thestiffening tube 28, along with the braided outer wall 26, providesimproved torsional stability while at the same time minimizing the wallthickness of the catheter, thus maximizing the diameter of the centrallumen 24. The outer diameter of the stiffening tube 28 is about the sameas or slightly smaller than the inner diameter of the outer wall 26.

The outer diameter of the catheter shaft 12 is not critical, but ispreferably no more than about 8 french, more preferably 7 french.Likewise the thickness of the outer wall 26 is not critical, but is thinenough so that the central lumen 24 can accommodate an infusion tube, apuller wire, lead wires, and any other wires, cables or tubes.

The distal region 22 of the catheter shaft 12 comprises a short sectionof tubing having three lumens. The first lumen 30 a electrode carrieslead wires, the second lumen 32 a carries a puller wire, and the thirdlumen 34 a carries an infusion tube, as described in more detail below.The tubing of the distal region 22 is made of a suitable non-toxicmaterial that is preferably more flexible than the proximal region 20. Apresently preferred material for the distal region 22 is braidedpolyurethane, i.e., polyurethane with an embedded mesh of braidedstainless steel or the like. The number and sizes of the lumens are notcritical and will depend on the components to be carried by the lumens.

As noted above, the proximal region 20 and distal region 22 havedifferent degrees of flexibility to enhance deflection of the distalregion of the catheter shaft. However, if deflection of the distalregion is less important, the catheter shaft can have a single stiffnessalong its length. With such a design, the proximal and distal regionscan be made, for example, of a single piece of tubing having only asingle lumen extending therethrough. Other catheter shaft arrangementswill be apparent to one skilled in the art and are within the scope ofthe invention.

At the distal end of the distal region 22 of the catheter shaft 12 isthe intermediate shaft 14, which carries the hinge, and the distal shaft16, which carries one or more electrodes or other diagnostic ortreatment devices. Specifically, as best shown in FIG. 3, theintermediate shaft 14 comprises a flexible plastic tubing, preferablyPEBAX. The distal shaft 16 similarly comprises a flexible plastictubing, preferably PEBAX. The intermediate shaft 14 is more flexiblethan either of the distal region 22 of the catheter shaft 12 or thedistal shaft 16 so as to not limit the ability of the intermediate shaftto bend, thereby allowing the hinge to control the extent and directionof bending of the intermediate shaft, as discussed further below. Unlikethe tubing that forms the catheter shaft 12, the plastic tubing thatforms the intermediate shaft 14 preferably does not include a braidedcore within the plastic. In one exemplary embodiment, the proximalregion 20 comprises 72D durometer plastic, the distal region 22comprises 55D durometer plastic, the intermediate shaft 14 comprises 35Ddurometer plastic, and the distal shaft 16 comprises 72D durometerplastic. The intermediate shaft 14 is connected to the distal end of thedistal region 22 of the catheter shaft 12 and to the proximal end of thedistal shaft 16 by any suitable method, for example, using thermal buttjoints.

In the depicted embodiment, the intermediate shaft 14 includes first,second and third lumens 30 b, 32 b, and 34 b that are aligned with thefirst, second and third lumens 30 a, 32 a, and 34 a, respectively, inthe distal region 22 of the catheter shaft 12. Similarly, the distalshaft 16 includes first, second and third lumens 30 c, 32 c, and 34 cthat are aligned with the first, second and third lumens 30 b, 32 b, and34 b, respectively, of the intermediate shaft 14. As would be recognizedby one skilled in the art, the number and arrangement of lumens in theintermediate shaft 14 can vary, but the lumens in the intermediate shaftare preferably aligned with the lumens in the distal region 22 of thecatheter shaft 12 and in the distal shaft 16, as discussed furtherbelow.

A hinge 40 is mounted over the intermediate shaft 14 to control thedirection and extent of bending of the intermediate shaft. The hinge 40comprises a flexible tube, which can be made of any suitable material,such as Nitinol or plastic, having an outer wall 42 and an innerdiameter that is slightly larger than the outer diameter of theintermediate shaft 14 so that the hinge can be mounted on the outside ofthe intermediate shaft, as shown in FIGS. 3 and 4. In the depictedembodiment, the hinge 40 covers the entire intermediate shaft 14 toreduce the tendency of the intermediate shaft to kink when the hinge isbent. The hinge 40 includes one or more slots 44 extending through theouter wall 42 of the flexible tube, which affect the direction in whichand extent to which the hinge can bend.

In the depicted embodiment, the slots 44 of the hinge 40 are arranged topermit the hinge to bend in a single plane in a single direction and nomore than approximately 90°. With reference to FIGS. 5 and 6, the outerwall 42 of the hinge 40 has a compressible side 46 and an expandableside 48. The compressible side 46 is the side facing the directiontoward which the hinge 40 bends, where the bending results in thecompressible side of the hinge being compressed on itself. Theexpandable side 48 is the side opposite the compressible side 46.

The depicted hinge 40 includes a total of fourteen slots 44 dividedevenly between the compressible side 46 and the expandable side 48. Whenthe hinge is in the neutral position, which in the depicted embodimentis straight, as shown in FIGS. 5 to 8, each slot 44 is generallyperpendicular to the axis of the hinge 40, although the slots couldalternatively be angled relative to the axis of the hinge so long asthey are generally transverse to the axis of the hinge. The slots 44 onthe compressible side 46 (“the compressible slots 44 a”) are alignedwith the slots 44 on the expandable side 48 (“the expandable slots 44b”), i.e., arranged so that corresponding slots on the compressible sideand on the expandable side are positioned the same distance from an endof the hinge. As will become apparent, the number, placement, size andshape of the slots 44 can vary depending on the desired effect to beachieved. Preferably the total number of slots on the hinge ranges fromone to about thirty, more preferably from about ten to about twenty. Theslots 44 can be provided only on the compressible side 46, only on theexpandable side 48 or divided in any desired manner between the twosides.

In the depicted embodiment, the slots 44 are all the same depth Q, i.e.,they all extend the same distance through the outer wall 42 of the hinge40 towards the axis of the hinge. The depicted slots do not extendthrough the axis or center of the hinge 40, so that the depth of eachslot is less than the outer radius of the hinge. If desired, the slotscan be deeper than the outer radius of the hinge so that they extendthrough the axis of the hinge 40, although with such a design it ispreferred that the compressible slots 44 a not be aligned with theexpandible slots 44 b, but instead alternate in position. If desired,the compressible slots 44 a can have depths different from those of theexpandible slots 44 b. In another alternative, the compressible slots 44a of a single hinge can have varying depths and/or the expandible slots44 b can have varying depths.

The shapes of the slots 44 can affect the extent to which the hinge 40will bend. In the depicted embodiment, the compressible slots 44 a aregenerally keyhole-shaped when viewed from the side, as best shown inFIG. 8. Specifically, each compressible slot 44 a comprises an elongatedopening 50 having two ends of decreasing width and that terminate incircular openings 52, which are preferably larger in diameter than thewidest portion of the elongated opening. Thus, the compressible slots 44a involve the removal of material from the flexible tube that forms thehinge. In one embodiment, each elongated opening 50 decreases in widthat an angle of 13°, varying from a maximum width of 0.011 inch to an endwidth (near the circular openings 52) of 0.006 inch, with the circularopening having a diameter of 0.020 inch, and with the distance D1between the compressible slots 44 a being approximately 0.021 inch.

Each expandible slot 44 b comprises an elongated slot 54 ofinsignificant thickness, i.e., where no material is removed from theflexible tube, that terminates in a circular opening 56 like thecircular openings 52 of the compressible slots 44 a. In one embodiment,the circular openings 56 of the expandible slots 44 b have the same sizeas the circular openings 52 of the compressible slots 44 a, with thedistance D2 between the expandible slots 44 b being approximately 0.032inch, so that the expandible slots 44 b are aligned with thecompressible slots 44 a.

In use, when a force is exerted on the distal shaft 16, which is mountedon the distal end of the hinge 40, the hinge is bent in a directiontoward the compressible side 46, as shown in FIG. 9. The arrangement ofthe slots 44 forces the hinge to bend within the desired plane. As thehinge 40 bends, the compressible slots 44 a are compressed so that theinwardly-angled openings 50 close, and the expandible slots 44 b expandso that the elongated slots 54 of insignificant thickness open, as bestdepicted in FIG. 9. The inwardly-angled openings 50 are sized asdescribed above such that they close and make further bending verydifficult once the hinge 40 reaches a 90° angle. Because the expandibleslots 44 b comprise elongated slots 54 of insignificant thickness whenthe hinge is in the neutral position, it is difficult for the hinge tobend in a direction toward the expandible side 48. Accordingly, thedepicted hinge 40 is designed to bend in a single plane in a singledirection and no more than approximately 90°.

The integrity of the hinge 40 is maintained by including a flexiblehinge cover 60 over the hinge. The hinge cover 60 is preferably made ofa biocompatible plastic, such as polyurethane, with a flexibilityapproximately equal to that of the intermediate shaft 14. The hingecover 60, like the intermediate shaft 14, should not limit the abilityof the hinge 40 to bend. The hinge cover 60 protects the hinge 40against electrical conductivity, particularly when the hinge is made ofNitinol or another metal, and also protects against blood and otherbodily fluids from entering and clogging the slots 44 of the hinge. Thehinge cover 60 is longer than the hinge 40 and has proximal and distalends extending beyond the hinge's proximal and distal ends,respectively. The hinge cover 60 can be secured in place over the hinge40 by any suitable method, such as by gluing or thermally bonding theproximal end of the hinge cover 60 to the distal region 22 of thecatheter shaft 12 and by gluing or thermally bonding the distal end ofthe hinge cover to the distal shaft 16.

Although the hinge 40 is described as being mounted over theintermediate shaft 14, it could also be mounted within the intermediateshaft, for example, if the intermediate shaft has a single centrallumen. Other arrangements for the hinge are also within the scope of theinvention. For example, the hinge can be formed by providing slotsdirectly into a portion of the tubing that forms the catheter shaft

As noted above, the distal shaft 16 carries one or more electrodes formapping and/or treatment or other treatment or diagnosis devices. In thedepicted embodiment, the distal shaft 16 carries a porous electrodearrangement comprising a coil electrode 62 wrapped around a portion ofthe distal shaft over which is mounted a plastic sleeve 64.

The coil electrode 62 can be made of any electrically-conductivematerial, such as platinum or gold. The length of the coil electrode 62can vary depending on the desired application, and preferably rangesfrom about 5 mm to about 20 mm, more preferably about 11 mm.

The porous sleeve 64 can be made of any suitable biocompatible porousmaterial through which fluid can pass, such as porouspolytetrafluoroethylene. Preferably the porous sleeve 64 is sufficientlyporous to permit saline to pass therethrough at a flowrate of at least 1cc/min, more preferably from about 10 cc/min to about 60 cc/min, stillmore preferably from about 20 cc/min to about 40 cc/min.

One or more irrigation openings 66 are provided in the wall of thedistal shaft 16 that fluidly connect the third lumen 34 c of the distalshaft to the outside of the distal shaft. In the depicted embodiment,the distal shaft 16 includes three irrigation openings 66, although thisnumber can vary as desired. The irrigation openings 66 are providedbetween the coils of the coiled electrode 62 and underneath the poroussleeve 64. The irrigation openings 66 permit fluid to pass from thethird lumen 34 c of the distal shaft to the outside of the distal shaftwithin the porous sleeve 64 and then through the porous sleeve. Thefluid is preferably saline or other conductive fluid so that current canpass from the coiled electrode 62 and through the fluid so that thefluid can be used to ablate tissue. The proximal and distal ends of theporous sleeve 64 can be attached to the distal shaft 16 by any suitablemethod that provides a fluid-tight seal to prevent fluid from leakingout the ends of the porous sleeve. In one embodiment, a plastic thread(not shown), such as a Dacron® thread, is wrapped and cinched around theends of the porous sleeve 64 and then sealed with polyurethane glue orthe like. Such a porous electrode arrangement is described in moredetail in U.S. patent application Ser. No. 09/073,907, entitled“Irrigated Ablation Device Assembly,” the entire disclosure of which isincorporated herein by reference.

To introduce saline or other fluid to the irrigation openings 66, aninfusion tube 68 is provided within the catheter shaft 12. The infusionfluid 68 has a distal end mounted in the proximal end of the third lumen34 a in the distal region 22 of the catheter shaft 12, and a proximalend that extends outside the catheter through the control handle 18, butcould alternatively extend out through a sidearm, as is generally knownin the art. A luer hub 69 is mounted on the proximal end of the infusiontube 68 so that fluid can be introduced into the infusion tube, throughthe third lumen 34 a in the distal region 22 of the catheter shaft 12,through the third lumen 34 b of the intermediate shaft 14, through thethird lumen 34 c of the distal shaft 16 and out through the irrigationopenings 66. In the depicted embodiment, the distal end of the distalshaft 16 is sealed with polyurethane glue or the like to prevent fluidfrom passing out through the distal end of the third lumen 34 c,although other mechanisms for closing the distal end of the distal shaftcan also be used.

Additionally, an electrode lead wire 70 is provided to electricallyconnect the coil electrode 62 to a source of radio frequency (RF) energyor other type of ablation energy. The electrode lead wire 70 extendsthrough the central lumen 24 of the proximal region 20 of the cathetershaft 12, through the first lumen 30 a of the distal region 22 of thecatheter shaft, through the first lumen 30 b of the intermediate shaft14, through the first lumen 30 c of the distal shaft 16, and out througha lead wire opening (not shown) in the distal shaft. Within the centrallumen 24 of the catheter shaft 12, the lead wire 70 extends through aprotective tube 71 to prevent the lead wire from interfering with othercomponents in the central lumen, although the protective tube can beeliminated if desired. Preferably the lead wire opening is potted withpolyurethane glue or the like to prevent fluid from passing into thefirst lumen 30 c through the lead wire opening. The distal end of thelead wire 70 is then soldered, welded or otherwise electricallyconnected to the underside of the coil electrode 62. The proximal end ofthe lead wire 70 extends through the control handle 18 and is connectedto a suitable connector (not shown), which can be part of the controlhandle, that is connected to a source of ablation energy, as isgenerally known in the art.

In the depicted embodiment, the distal shaft 16 also carries four ringelectrodes 72, although the presence and number of the ring electrodescan vary as desired. The ring electrodes 72 are particularly useful formapping electrical activity within the heart and can be electricallyconnected to an appropriate monitoring apparatus (not shown) as isgenerally known in the art. Two ring electrodes 72 are mounted distal tothe coil electrode 62, and the other two are mounted proximal to thecoil electrode, all within the porous sheath 64. Alternatively, the ringelectrodes 72 can be mounted over the proximal and distal ends of poroussheath 64 so long as they do not extend over the region over which thecoil electrode 62 extends. Lead wires 70 electrically connect the ringelectrodes 72 to a monitoring apparatus in a manner similar to theconnection of a lead wire to the coil electrode or in any other mannerknown to those skilled in the art.

One or more thermocouples 74 can also be provided for monitoring thetemperature of the tissue being ablated. In the depicted embodiment, twothermocouples 74 are provided, one just proximal to the coiled electrode62 and one just distal to the coiled electrode. In addition or in thealternative, thermocouples could be provided in other locations, such asbetween the coils of the coiled electrode, or eliminated altogether.Each thermocouple comprises a pair of thermocouple wires 74 that extend,along with the lead wires 70, through the central lumen 24 of theproximal region 20 of the catheter shaft 12, through the first lumen 30a of the distal region 22 of the catheter shaft, through the first lumen30 b of the intermediate shaft 14, through the first lumen 30 c of thedistal shaft 16 and out through a thermocouple opening (not shown) inthe distal shaft. The thermocouple openings are preferably potted withpolyurethane glue or the like to hold the thermocouples 74 in place andto prevent fluid from passing into the first lumen 30 c of the distalshaft 16.

As would be recognized by one skilled in the art, the distal shaft 16can carry a variety of other electrode configurations. Otherparticularly useful electrode configurations for use with the inventivehinge design are described in U.S. Pat. No. 6,371,955, U.S. patentapplication Ser. No. 09/551,467, entitled “Catheter Having MappingAssembly,” U.S. patent application Ser. No. 10/107,899, entitled“Bidirectional Catheter Having Mapping Assembly,” and U.S. patentapplication Ser. No. 10/118,680, entitled “Catheter Having CircularAblation Assembly,” the entire disclosures of which are incorporatedherein by reference. The distal shaft 16 could also carry othermeasurement and/or treatment devices, such as optic fibers, needles orballoons. The particular measurement or treatment device carried by thecatheter is not critical to the invention.

The catheter can also include a mechanism for deflecting the distalregion 22 of the catheter shaft 12. In the depicted embodiment, a pullerwire 76 extends through proximal region 20 of the catheter shaft 12, isanchored at its proximal end to the control handle 18, and is anchoredat its distal end to the distal region 22 of the catheter shaft. Thepuller wire 76 is made of any suitable metal, such as stainless steel orNitinol, and is preferably coated with Teflon® or the like. The coatingreduces the surface friction on the puller wire 76 during deflection.

A compression coil 78 is situated within the proximal region 20 of thecatheter shaft 12 in surrounding relation to the puller wire 76. Thecompression coil 78 extends from the proximal end of the catheter shaft12 to the proximal end of the distal region 22 of the catheter shaft.The compression coil 78 is made of any suitable metal, preferablystainless steel. The compression coil 78 is tightly wound on itself toprovide flexibility, i.e., bending, but to resist compression. The innerdiameter of the compression coil 78 is preferably slightly larger thanthe diameter of the puller wire 76. The Teflon® coating on the pullerwire 76 allows it to slide freely within the compression coil 78. Ifdesired, the outer surface of the compression coil 78 is covered by aflexible, non-conductive sheath 80, e.g., made of polyimide tubing, toprevent contact between the compression coil and the lead wires and/orthermocouple wires within the catheter shaft 12.

The compression coil 78 is anchored at its proximal end to the outerwall 26 of the catheter shaft 12 by proximal glue joint 82 and at itsdistal end to the distal region 22 by distal glue joint 84. Both gluejoints 82 and 84 preferably comprise polyurethane glue or the like. Theglue may be applied by means of a syringe or the like through a holemade between the outer surface of the catheter shaft 12 and the centrallumen 24.

The puller wire 76 extends into the second lumen 32 a of the distalregion 22 of the catheter shaft 12. Preferably the puller wire 76 isanchored at its distal end to the side of the distal region 22, as shownin FIGS. 11 to 13. A T-shaped anchor 86 is formed which comprises ashort piece of tubular stainless steel 88, e.g., hypodermic stock, whichis fitted over the distal end of the puller wire 76 and crimped tofixedly secure it to the puller wire. The distal end of the tubularstainless steel 88 is fixedly attached, e.g., by welding, to a stainlesssteel cross-piece 90, such as stainless steel ribbon or the like. Thecross-piece 90 sits in a notch 92 in a wall of the distal region 22 thatextends into the second lumen 32 a. The stainless steel cross-piece 90is larger than the notch 92 and, therefore, cannot be pulled through thenotch. The portion of the notch 92 not filled by the cross-piece 90 isfilled with glue or the like, preferably a polyurethane glue, which isharder than the material of the distal region 22. Rough edges, if any,of the cross-piece 90 are polished to provide a smooth, continuoussurface with the outer surface of the distal region 22. Within thesecond lumen 32 a of the distal region 22, the puller wire 76 extendsthrough a plastic, preferably Teflon®, puller wire sheath 94, whichprevents the puller wire 76 from cutting into the wall of the distalregion 22 when the distal region is deflected. Any other suitabletechnique for anchoring the puller wire 76 in the distal region 22 canalso be used. Alternatively, other means for deflecting the distalregion can be provided, such as the deflection mechanism described inU.S. Pat. No. 5,537,686, the disclosure of which is incorporated hereinby reference.

Longitudinal movement of the puller wire 76 relative to the proximalregion 20 of the catheter shaft 12, which results in deflection of thedistal region 22, is accomplished by suitable manipulation of thecontrol handle 18. Examples of suitable control handles for use in thepresent invention are disclosed, for example, in U.S. Pat. Nos. Re34,502 and 5,897,529, the entire disclosures of which are incorporatedherein by reference. However, the precise structure of the controlhandle is not critical so long as it is capable of manipulating thepuller wire or other means for deflecting the distal region.

If desired, two or more puller wires can be provided to enhance theability to manipulate the tip section. In such an embodiment, a secondpuller wire and a surrounding second compression coil extend through thecatheter body and into an additional off-axis lumen in the tip section.The first puller wire is preferably anchored proximal to the anchorlocation of the second puller wire. Suitable designs of catheters havingtwo or more puller wires, including suitable control handles for suchembodiments, are described, for example, in U.S. Pat. Nos. 6,171,277,6,123,699, 6,183,463, and 6,198,974, the disclosures of which areincorporated herein by reference.

Because in the depicted embodiment the puller wire 76 terminates in thecatheter shaft 12, the second lumens 32 b and 32 c of the intermediateshaft 14 and the distal shaft 16 are empty. However, if desired, thepuller wire 76 could instead be anchored in the distal shaft 16 inmanner essentially identical to that described above with respect to thedistal region 22 of the catheter shaft 12 so as to permit the use toactively deflect the distal shaft. Alternatively, separate puller wires(not shown) could be provided for deflection of the distal region 22 ofthe catheter shaft 12 and for deflection of the distal shaft 16.

In use, a suitable guiding sheath is inserted into the patient. Anexample of a suitable guiding sheath for use in connection with thepresent invention is the Preface™ Braided Guiding Sheath, commerciallyavailable from Biosense Webster (Diamond Bar, Calif.). The distal end ofthe sheath is guided into one of the atria or other region of the heart.A catheter according to the present invention is fed through the guidingsheath until its distal end extends out of the distal end of the guidingsheath.

Once inside the heart, the distal shaft is positioned for the desiredmapping or treatment procedure. If the distal shaft carries a porouselectrode, the porous electrode can then be used to form continuouslinear lesions by ablation. If the distal shaft carries other electrodearrangements, the electrodes can be used for ablating or mapping, asdesired. If the distal shaft carries some other component, such as aballoon or optic fiber, that other component can be used for diagnosisand/or treatment as is generally known in the art. The positioning ofthe distal shaft can be performed by simply pushing the distal shaftagainst the heart tissue to thereby cause the distal shaft to deflect orbend toward the catheter shaft. The presence of the hinge will enhancethe ability of the distal shaft to bend in a single plane in the desireddirection and can also limit the extent to which the distal shaft bends.Alternatively, if a puller wire or other deflection mechanism isprovided within the distal shaft, the user can actively deflect or bendthe distal shaft, with the hinge again serving to enhance the ability ofthe distal shaft to bend in a single plane in the desired direction andoptionally limit the extent to which the distal shaft bends.

The preceding description has been presented with reference to presentlypreferred embodiments of the invention. Workers skilled in the art andtechnology to which this invention pertains will appreciate thatalterations and changes in the described structure may be practicedwithout meaningfully departing from the principal, spirit and scope ofthis invention.

Accordingly, the foregoing description should not be read as pertainingonly to the precise structures described and illustrated in theaccompanying drawings, but rather should be read consistent with and assupport to the following claims which are to have their fullest and fairscope.

What is claimed is:
 1. A method of mapping or ablating tissue, themethod comprising: positioning a deflectable device near the tissue, thedeflectable device having proximal and distal ends and comprising: anelongated tubing having proximal and distal ends, an axis, at least onelumen extending therethrough, a distal region at or near the distal endof the deflectable device, and an intermediate region proximal of thedistal region, wherein the tubing includes a hinge region comprising anexpandible side and a compressible side opposite the expandible side,the hinge region further comprising at least one first slot extendingpart of the way through the tubing on the expandible side, and at leastone second slot extending part of the way through the tubing on thecompressible side, the at least one first slot and the at least onesecond slot being generally transverse to the axis of the tubing, the atleast one first slot having a first thickness and the at least onesecond slot having a second thickness, wherein the first and secondthicknesses are different from one another when the hinge region is in aneutral straight position, wherein the hinge region of the tubing isadapted to reversibly bend from the neutral straight position in a firstdirection in only a single plane and in only a single direction asdefined by the at least one first slot and the at least one second slotand adapted to prohibit bending from the neutral straight position in asecond direction opposite the first direction; and activating the hingeregion of the tubing to thereby deflect the intermediate region of thetubing in the first direction.
 2. The method according to claim 1,wherein the deflectable device further comprises: a control handle atthe proximal end of the elongated tubing; and a puller wire having adistal end anchored in the intermediate region of the tubing and aproximal end anchored in the control handle, wherein the activating thehinge region comprises manipulating the control handle to move thepuller wire longitudinally to thereby deflect the intermediate region ofthe tubing.
 3. The method according to claim 1, wherein the activatingthe hinge region comprises contacting the distal region of the tubingwith the tissue to thereby deflect the intermediate region of thetubing.
 4. A method of mapping or ablating tissue, the methodcomprising: positioning a distal region of a deflectable device near thetissue, the deflectable device having proximal and distal ends andcomprising: a proximal region near the proximal end of the device, adistal region near the distal end of the device, and a hinge between theproximal and distal regions, the hinge comprising a tubing having anaxis and at least one lumen extending therethrough, wherein the tubingincludes an expandible side and a compressible side opposite theexpandible side, at least one first slot extending part of the waythrough the tubing on the expandible side and at least one second slotextending part of the way through the tubing on the compressible side,the at least one first slot having a first thickness and the at leastone second slot having a second thickness, wherein the first and secondthicknesses are different from each other when the tubing is in aneutral straight position, such that the hinge is adapted to reversiblybend from the neutral straight position in a first direction in only asingle plane and in only a single direction as defined by the at leastone first slot and the at least one second slot and adapted to prohibitbending from the neutral straight position in a second directionopposite the first direction; and activating the hinge to therebydeflect the hinge in the first direction.
 5. The method according toclaim 4, wherein the deflectable device further comprises: a controlhandle at the proximal end of the device; and a puller wire having adistal end anchored in the hinge and a proximal end anchored in thecontrol handle, wherein activating the hinge comprises manipulating thecontrol handle to move the puller wire longitudinally to thereby deflectthe hinge.
 6. The method according to claim 4, wherein the activatingthe hinge comprises contacting the distal region of the device with thetissue to thereby deflect the hinge.
 7. A method of mapping or ablatingtissue, the method comprising: positioning a distal segment of adeflectable catheter near the tissue, the deflectable cathetercomprising: an elongated tubular catheter body having proximal anddistal ends and at least one lumen extending therethrough, a distalsegment distal to the distal end of the catheter body, the distalsegment having proximal and distal ends, and a tubular hinge between thedistal end of the catheter body and the proximal end of the distalsegment, the hinge having an axis and at least one lumen extendingtherethrough, wherein the hinge includes an expandible side and acompressible side opposite the expandible side, at least one first slotextending part of the way through the hinge on the expandible side, atleast one second slot extending part of the way through the hinge on thecompressible side, the at least one first slot and the at least onesecond slot being generally transverse to the axis of the hinge, the atleast one first slot having a first thickness and the at least onesecond slot having a second thickness, wherein the first and secondthicknesses are different from each other when the hinge is in a neutralstraight position such that the hinge is adapted to reversibly bend fromthe neutral straight position in a first direction in only a singleplane and in only a single direction as defined by the at least onefirst slot and the at least one second slot and adapted to prohibitbending from the neutral straight position in a second directionopposite the first direction; and activating the hinge to therebydeflect the hinge in the first direction.
 8. The method according toclaim 7, wherein the activating the hinge comprises contacting thedistal segment of the tubing with the tissue to thereby deflect thehinge.
 9. The method according to claim 7, wherein the deflectablecatheter further comprises: a control handle at the proximal end of thecatheter; and a puller wire having a distal end anchored in the hingeand a proximal end anchored in the control handle, wherein activatingthe hinge comprises manipulating the control handle to move the pullerwire longitudinally to thereby deflect the hinge.
 10. The methodaccording to claim 7, wherein the at least one first slot and the atleast one second slot are generally perpendicular to the axis of thehinge.
 11. The method according to claim 7, wherein the at least onefirst slot or the at least one second slot includes a number of slotsranging from 10 to
 20. 12. The method according to claim 7, wherein theat least one first slot or the at least one second slot includes aplurality of slots, each slot having a depth such that the slot does notpass through the axis of the hinge.
 13. The method according to claim 7,wherein the at least one first slot or the at least one second slotincludes a plurality of slots of equal depth.
 14. The method accordingto claim 7, wherein each slot of the at least one second slot along thecompressible side comprises an elongated opening having a center widthand two ends having widths less than the center width.
 15. The methodaccording to claim 14, wherein each end of each elongated openingterminates in a circular opening, the circular openings having diametersgreater than the widths of the ends of the elongated openings.
 16. Themethod according to claim 7, wherein the at least one first slot alongthe expandible side is aligned with the at least one second slot alongthe compressible side.
 17. The method according to claim 7, wherein thecatheter further comprises a porous electrode on the distal segment andmeans for irrigating the porous electrode, and the method furthercomprises irrigating the porous electrode.